Action of lnhibitor in Serum of Patients with Myasthenia Gravis on Acetylcholine Synthesis
スポンサーリンク
概要
- 論文の詳細を見る
It is generally considered that the disease process in myasthenia gravis involves a defect at the neuromuscular junction, but the entity remains obscure. Possible mechanisms of the defect in neuromuscular transmission are 1) inhibition of presynaptic acetylcholine (Ach) synthesis, 2) increased hydrolysis of released Ach, and 3) decreased sensitivity of Ach receptor. Many workers reported that prejunctional and postjunctional defects might be caused by a substance present in blood of patients with myasthenia gravis. We found that serum of myasthenic patients inhibits the Ach synthesis, and studied on some properties of theinhibitor.<BR>Inhibition of the Ach synthesis by addition of either serum of normal persons or myasthenic patients were examined by using both slices and homogenate of rat brain cortex. Assays of Ach formed were carried out on the rectus abdominis muscle of a frog.<BR>Inhibition of the Ach synthesis increases approximately in parallel with concentration of serum in the reaction mixture, which means the presence of an inhibitory substance in serum of the patients. The supernatant of boiled serum of the patients (boiled sup of serum) inhibits the Ach synthesis to the same extent as untreated serum. While the inhibitory effect decreases when the boiled sup of serum is treated with acid (pH 2.0), it almost disappears when treated with alkali (pH 10.0). The inhibitor is not extracted by chloroform-methanol (2: 1) and the inhibition by the boiled sup is not affected by this treatment.<BR>The serum of the patients was fractionated to three parts by means of Sephadex G-50 column; I: fraction including protein, II: intermediate fraction, III: fraction including salts. Fraction I shows the inhibition of 17.5%, and fraction II that of 7.1%, but fraction III no inhibition. In case of the boiled sup of serum, however, the inhibitionis observed only in fraction II by 12.5%. It is postulated that the inhibitor in the patients' serum has the nature to bind with protein and has particularly labile structures againstalkali, and that the substance may be amine or peptide.<BR>When the Ach synthesis is carried out by the method of Gardiner with a water-treated and ultracentrifuged (105,000×g, 60min) preparation of rat brain cortex inthe reaction mixture containing acetyl-CoA, the patients' serum has also an inhibitory effect of 20-27%. This result suggests that the inhibition of the Ach synthesis is closely related to cholineacetylase rather than membrane transport, and the inhibitor of the Ach synthesis in rat brain cortex may have the same activity at the neuromuscular junction, too.
- Japan Society of Clinical Chemistryの論文
著者
関連論文
- 241 食道静脈瘤出血に対する PTO の経験(第13回日本消化器外科学会総会)
- 564 進行膵癌切除症例の生命予後と Quality of Life の評価 : 各種術式の比較評価(第39回日本消化器外科学会総会)
- 門脈・肝動脈血行再建を伴う膵全摘術後長期生存した膵癌の1症例
- 病型分類からみた肝内結石症に対する手術術式の選択についての検討
- WIV-15 自家部分膵移植の臨床的検討(第31回日本消化器外科学会総会)
- 示-36 消化管粘膜下腫瘍71例の臨床病理学的検討(第37回日本消化器外科学会総会)
- 204 肝切除術後 GOT isozyme の血中動態ならびに肝組織中含有量の臨床的意義(第31回日本消化器外科学会総会)
- 425 虚血肝症例における m-GOT の漏出動態と肝不全の関係(第28回日本消化器外科学会総会)
- 肺転移巣切除により発見され, 原発巣切除後6年生存中の肝細胞癌の1例
- 63 肝切除術施行症例における血中 m-GOT 値の変動(第27回日本消化器外科学会総会)
- 455 膵Gastrinomaの1手術例(第18回日本消化器外科学会総会)
- 428 Budd-Chiari 症候群手術例における術後肝機能障害と術前肝体積の関連(第38回日本消化器外科学会総会)
- 示-133 脾外進展型の脾原発悪性リンパ腫の2治癒切除例(第29回日本消化器外科学会総会)
- S-I-5 心奇形を伴なう新生児外科手術症例の検討
- Budd-Chiari症候群に対する直視下根治術後の肝部下大静脈再狭窄に対する血管拡張術の2例
- Action of lnhibitor in Serum of Patients with Myasthenia Gravis on Acetylcholine Synthesis